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5 Table of Contents " Section 1 Introduction 1-1 Section 2 Model Description Basic Equations Henrick Eddy Model Empirical Estimation of Model Parameters 2-8 Section 3 Data 3-1 Section 4 Model Results 4-1 Section 5 Model Comparative Statistics 5-1 Section 6 Model Summary 6-1 Section 7 Acoustics 7-I 7.1 Introduction Cold Eddy 20 Hz Warm Eddy 20 Hz Cold Eddy 300 Hz Warm Eddy 300 Hz Cold Eddy 1000 Hz Frequency Effects 7-29 Section 8 Acoustics Comparative Statistics 8-1 Section 9 Conclusions 9-1 Section 10 Summary 10-1 Acknowledgements * References R-1 Appendix A Track Isovelocity and Isothermal Contours Appendix B Distribution C-i A-I B-I * I.. o.
8 page Figure 27 Transmission loss vs. Range Cold Eddy Hz Receiver Depth: 900 m 60 km average * Figure 28 Transmission loss vs. Range Warm Eddy 300 Hz Receiver Depth: 95 m km average Figure 29 Transmission loss vs. Range Warm Eddy Hz Receiver Depth: 95 m unaveraged Figure 30 Transmission loss vs. Range Warm Eddy Hz Receiver Depth: 450 m 60 km average Figure 31 Transmission loss vs. Range Warm Eddy Hz Receiver Depth: 700 m 60 km average Figure 32 Transmission loss vs. Range Warm Eddy Hz Receiver Depth: 900 m 60 km average Figure 33 Transmission loss vs. Range Cold Eddy Hz Receiver Depth: 95  60 km average * Figure 34 Transmission loss vs. Range Cold Eddy Frequency Effects Receiver Depth: 95 m km average Figure 35 Comparative Intensity Statistics 8-2 Cold Eddy 20 Hz km Figure 36 Comparative Intensity Statistics 8-4 Cold Eddy 20 Hz km Figure 37 Comparative Intensity Statistics 8-5 Cold Eddy 20 Hz km Figure 38 Comparative Intensity Statistics 8-6 Cold Eddy 20 Hz km Figure 39 Comparative Intensity Statistics 8-7 Warm Eddy 20 Hz km Figure 40 Comparative Intensity Statistics 8-8 Warm Eddy 20 Hz km SI' iv ' " n *", - '- -, , r.., l,.... :# : :.
18 Y 2(1) Zn(l+Bzo) (10) This model uses dimensionless parameters scaled in the following manner. All horizontal ranges are scaled by a characteristic length scale, L. the depth of the ocean, D. All depths are scaled by The characteristic length scale is a function of D and S, where S is a dimensionless scaling constant. This scaling constant is a function of g, gravitational acceleration, co, surface sound velocity, and the Coriolis parameter, 2 2sinO. For example, the dimensionless horizontal range used in the eddy model is found by scaling the dimensional range, denoted by the star(*), by the characteristic length scale. L f DS L - Characteristic Length Scale (m) ro "-L' r fir* L D - Ocean Depth (m) S g (Dimensionless) 20 sino = latitude g = 9.8 m sec - 2 c o = surface sound velocity L z._ 2 * Z Z * 0 D D (m sec - ) = earth's angular velocity x 10-5 sec m - "
35 Eddy Model Isovelocity Contours for Cold-Core Eddy Figure 8 I7 3 I I~9C) Z E KM.5..
40 Eddy Model Isothermal and Isovelocity Sections for Warm-Core Eddy Figure 12!. C , ,, * I CD 2 C C IS 1! RANGE. A h) RR.NGE. I,,MI.
47 Section 7 ACOUSTIC ANALYSIS 7.1. Introduction The underlying purpose behind the following acoustic analysis is to assess the acoustic impact of mesoscale fluctuations as a function of varying sourcereceiver geometry and source frequency. To that end, two tracks have been constructed for use in propagation modeling. The tracks contain the static or background sound velocity profiles at their start. The background profiles are extended for 185 km. Immediately following this rangeindependent 185 km is a section of track containing an eddy, either the warm-' or cold-core eddy from the Schenectady or Bristol County track, respectively. The diameter of both eddies was appioximately 370 km. Following the eddy, there is another 185 km of background sound velocity conditions. We therefore have constructed two acoustic tracks, consisting of 185 km of range-independent conditions, followed by 370 km of track containing an eddy (warm or cold), followed by an additional 185 km of range-independent track. For comparative purposes, a totally range-independent track has been constructed, where the background sound velocity profile which exists at 0 km is extended for the length of the track, in this instance 740 km. To evaluate the impact of varying source-receiver geometry, we have selected four different situations. The first has the source located at 0 km at the start of the totally range-independent track. The second geometry has * 7-1.
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